Buggy code:
public class BarcodeAction extends BaseAction { private static final long serialVersionUID = 8920999609104602879L ; private List < PurchaseOrderDetail > purchaseOrderDetails ; private PurchaseOrderDetail purchaseOrderDetail ; private InputStream inputStream ; private String fileName ; public List < PurchaseOrderDetail > getPurchaseOrderDetails ( ) { } public void setPurchaseOrderDetails ( List < PurchaseOrderDetail > purchaseOrderDetails ) { } public PurchaseOrderDetail getPurchaseOrderDetail ( ) { } public void setPurchaseOrderDetail ( PurchaseOrderDetail purchaseOrderDetail ) { } public InputStream getInputStream ( ) throws FileNotFoundException { } public String getFileName ( ) { } public String list ( ) { } private void query ( ) { } public String print ( ) { if ( ConnectQAD ( ) ) { String userCode = this . getRequest ( ) . getRemoteUser ( ) ; @ SuppressWarnings ( "unchecked" ) List < String > supplierCodeList = getSupplierCodeList ( ( ( purchaseOrderDetail ) != null ? purchaseOrderDetail . getTt_xpyhddeto_suppcode ( ) : "" ) ) ; String domain = getCurrentDomain ( ) ; ProDataGraph exDataGraph ; ProDataGraphHolder outputData = new ProDataGraphHolder ( ) ; try { exDataGraph = new ProDataGraph ( m_YFKSSSCPImpl . getXxprint_barcode_DSMetaData1 ( ) ) ; for ( int i = 0 ; i < ( supplierCodeList . size ( ) ) ; i ++ ) { ProDataObject object = exDataGraph . createProDataObject ( "tt_suppcode_in" ) ; String supCode = supplierCodeList . get ( i ) ; object . setString ( 0 , domain ) ; object . setString ( 1 , supCode ) ; exDataGraph . addProDataObject ( object ) ; } SimpleDateFormat df = new SimpleDateFormat ( "yyyyMMdd" ) ; String currDate = df . format ( new Date ( ) ) ; if ( ( purchaseOrderDetails ) != null ) { for ( PurchaseOrderDetail pod : purchaseOrderDetails ) { <START_BUG> if ( ( ( ( ( pod . getTt_xpyhddeto_lots ( ) ) != null ) && ( ( pod . getTt_xpyhddeto_lots ( ) ) != "" ) ) && ( ( pod . getTt_xpyhddeto_qty ( ) ) != null ) ) && ( ! ( pod . getTt_xpyhddeto_qty ( ) . equals ( BigDecimal . ZERO ) ) ) ) { <END_BUG> ProDataObject objectMstr = exDataGraph . createProDataObject ( "tt_bcdet_in" ) ; objectMstr . setString ( 0 , pod . getTt_xpyhddeto_partnbr ( ) ) ; objectMstr . setString ( 1 , pod . getTt_xpyhddeto_lots ( ) ) ; objectMstr . setBigDecimal ( 2 , pod . getTt_xpyhddeto_qty ( ) ) ; objectMstr . setString ( 3 , currDate ) ; objectMstr . setString ( 4 , pod . getTt_xpyhddeto_xpyhddetoid ( ) ) ; objectMstr . setString ( 5 , purchaseOrderDetail . getIsexternal ( ) ) ; exDataGraph . addProDataObject ( objectMstr ) ; } } } yfkssScp . xxprint_barcode ( exDataGraph , outputData ) ; @ SuppressWarnings ( "unchecked" ) List < ProDataObject > outDataList = ( ( List < ProDataObject > ) ( outputData . getProDataGraphValue ( ) . getProDataObjects ( "tt_bcdet_out" ) ) ) ; List < Barcode > barcodeList = QADUtil . ConvertToBarcode ( outDataList ) ; String localAbsolutPath = this . getSession ( ) . getServletContext ( ) . getRealPath ( "//" ) ; inputStream = PrintBarcodeUtil . printBarcode ( localAbsolutPath , barcodeList , userCode ) ; fileName = "barcode.pdf" ; } catch ( Exception e ) { } } return SUCCESS ; } public List < LabelValue > getPackageList ( ) { } }

Fix:
if ( ( ( ( ( pod != null ) && ( ( pod . getTt_xpyhddeto_lots ( ) ) != null ) ) && ( ( pod . getTt_xpyhddeto_lots ( ) ) != "" ) ) && ( ( pod . getTt_xpyhddeto_qty ( ) ) != null ) ) && ( ! ( pod . getTt_xpyhddeto_qty ( ) . equals ( BigDecimal . ZERO ) ) ) ) {